Stapler with composite cardan and screw drive

ABSTRACT

A surgical instrument is provided that includes a first jaw having a first jaw axis and that includes a proximal portion pivotally mounted to the base to be pivotable about a pivot axis between an open and a closed positions and including a distal portion; a second jaw having a second jaw axis and including a proximal portion secured to the base and including a distal portion; a first side edge secured to the first jaw a second side edge secured to the second jaw; a third side edge secured to the first jaw; a drive member including a cross-beam, which is sized to slideably engage the first, second and third side edges, a first transverse beam portion, and a second transverse beam portion; and a lead screw configured to advance the drive member in a distal direction parallel to the second jaw axis while engaging one or the other of the first and second side edges and the second side edge.

RELATED APPLICATIONS

This patent application is a U.S. National Stage Filing under 35 U.S.C.371 from International Application No. PCT/US2016/059527, filed on Oct.28, 2016, and published as WO 2017/083125 A1 on May 18, 2017, whichclaims priority to and the benefit of the filing date of U.S.Provisional Patent Application 62/255,123, entitled “STAPLER WITHCOMPOSITE CARDAN AND SCREW DRIVE” filed Nov. 13, 2015, each of which isincorporated by reference herein in its entirety.

BACKGROUND

Minimally invasive surgical techniques are aimed at reducing the amountof extraneous tissue that is damaged during diagnostic or surgicalprocedures, thereby reducing patient recovery time, discomfort, anddeleterious side effects. As a consequence, the average length of ahospital stay for standard surgery may be shortened significantly usingminimally invasive surgical techniques. Also, patient recovery times,patient discomfort, surgical side effects, and time away from work mayalso be reduced with minimally invasive surgery.

Minimally invasive teleoperated surgical systems have been developed toincrease a surgeon's dexterity when working on an internal surgicalsite, as well as to allow a surgeon to operate on a patient from aremote location (outside the sterile field). In a teleoperated surgicalsystem, the surgeon is often provided with an image of the surgical siteat a control console. While viewing a three dimensional image of thesurgical site on a suitable viewer or display, the surgeon performs thesurgical procedures on the patient by manipulating master input orcontrol devices of the control console. Each of the master input devicescontrols the motion of a servo-mechanically actuated/articulatedsurgical instrument. During the surgical procedure, the teleoperatedsurgical system can provide mechanical actuation and control of avariety of surgical instruments or tools having end effectors thatperform various functions for the surgeon, for example, holding ordriving a needle, grasping a blood vessel, dissecting tissue, staplingtissue, or the like, in response to manipulation of the master inputdevices.

SUMMARY

In one aspect, a surgical instrument a surgical instrument includes afirst jaw having a first jaw axis and that includes a proximal portionpivotally mounted to a base to be pivotable about a pivot axis betweenan open and a closed positions and including a distal portion. A secondjaw has a second jaw axis and includes a proximal portion secured to thebase and includes a distal portion. A first cam surface secured to thefirst jaw that includes a distal cam portion that extends parallel tothe first jaw axis and a proximal cam portion that is inclined at anangle relative to the distal cam portion. A second cam surface securedto the second jaw that extends parallel to the second jaw axis. A drivemember includes a cross-beam, which is sized to slideably engage thefirst and second cam surfaces, a first transverse beam portion, and asecond transverse beam portion. A lead screw configured to advance thedrive member in a distal direction parallel to the second jaw axis.While the first jaw is in the open position, the distal cam portion andthe second cam surface are disposed to contact the first and secondtransverse beam portions, respectively, and the distal cam portion isdisposed to impart a rotational force to the first jaw about the pivotaxis as the lead screw advances the drive member in the distaldirection. While the first jaw is in the closed position, the proximalcam portion and the second cam surface are disposed, to contact thefirst and second transverse beam portions, respectively, and to impart aclamp force to the first and second jaws as the lead screw advances thedrive member in the distal direction.

In another aspect, a universal double joint includes a first rotatablebearing has a first spherical surface formed of a plastic material. Atleast one first metal pin is configured to receive the imparted driveforce and to impart the imparted drive force to the first rotatablebearing. A second rotatable bearing has a second spherical surfaceformed of a plastic material. At least one second metal pin configuredto receive the imparted drive force and to impart the imparted driveforce to the second rotatable bearing.

BRIEF DESCRIPTION OF DRAWINGS

Aspects of the present disclosure are best understood from the followingdetailed description when read with the accompanying figures. It isemphasized that, in accordance with the standard practice in theindustry, various features are not drawn to scale. In fact, thedimensions of the various features may be arbitrarily increased orreduced for clarity of discussion. In addition, the present disclosuremay repeat reference numerals and/or letters in the various examples.This repetition is for the purpose of simplicity and clarity and doesnot in itself dictate a relationship between the various embodimentsand/or configurations discussed.

FIG. 1 is an illustrative plan view illustration of a teleoperatedsurgical system in accordance with some embodiments.

FIG. 2 is an illustrative perspective view of the Surgeon's Console inaccordance with some embodiments.

FIG. 3 is an illustrative perspective view of the Electronics Cart inaccordance with some embodiments.

FIG. 4 is an illustrative bock diagram diagrammatically representingfunctional relationships among components of a teleoperated surgerysystem in accordance with some embodiments.

FIGS. 5A-5B are illustrative drawings showing a Patient Side Cart and asurgical tool 62, respectively in accordance with some embodiments.

FIG. 6 is an illustrative drawing showing an example surgical tool inaccordance with some embodiments.

FIG. 7 is perspective view of a portion of a torque transmittingmechanism for transmitting torque through an angle, in accordance withsome embodiments.

FIG. 8 is an exploded perspective view of the torque transmittingmechanism of FIG. 1 in accordance with some embodiments.

FIG. 9 is a perspective partially cut away view of the torquetransmitting mechanism of FIGS. 7-8 shown as assembled in accordancewith some embodiments.

FIG. 10A is illustrative cross-sectional view of the torque transmittingmechanism of FIGS. 7-9 in an inline position in accordance with someembodiments.

FIG. 10B is illustrative cross-sectional view of the torque transmittingmechanism of FIGS. 7-9 in an articulated position in accordance withsome embodiments.

FIG. 11 is an illustrative cross-sectional view of the torquetransmitting mechanism of FIGS. 7-10B, illustrating the configuration ofthe proximal and distal transverse slots in accordance with manyembodiments.

FIG. 12A is an illustrative side elevation view of a torque transmittingmechanism along a view direction normal to the axes of coupling pins inaccordance with some embodiments.

FIG. 12B is an illustrative side elevation view of a torque transmittingmechanism along a view direction parallel to the axes of coupling pinsin accordance with some embodiments.

FIG. 13 is an illustrative drawing shows a portion of a torquetransmitting mechanism with the coupling member removed and a “seethrough” driven shaft plastic bearing to show the cross mounting of adistal coupling pin to a distal cross pin in accordance with someembodiments.

FIG. 14A is an illustrative perspective view showing details of proximaland distal cross pin bores of respective drive shaft plastic bearing anddriven shaft plastic bearing in accordance with some embodiments.

FIG. 14B is an illustrative perspective view showing details of proximaltransverse slot and the distal transverse slot of the respective driveshaft plastic bearing and driven shaft plastic bearing in accordancewith some embodiments.

FIG. 15 is an illustrative perspective drawing, with a partial cutaway,of a surgical tool assembly in accordance with some embodiments.

FIG. 16 is an illustrative perspective view, with a partial cutaway, ofthe end effector of FIG. 9 with an empty second jaw from which thestapler cartridge is removed in accordance with some embodiments.

FIG. 17 is an illustrative exploded view of a detachable stationarysecond jaw in accordance with some embodiments.

FIG. 18 is an illustrative cross sectional view of the end effector ofFIGS. 15-17 in accordance with some embodiments.

FIG. 19A is a top elevation view of the first cam surface in accordancewith some embodiments.

FIG. 19B is a cross-section view showing edges of one side of the firstcam surface in accordance with some embodiments.

FIG. 20 is an illustrative bottom elevation view of the longitudinallyextending second cam surface in accordance with some embodiments.

FIG. 21 is an illustrative perspective view of the drive member inaccordance with some embodiments.

FIGS. 22A-22F are schematic cross-sectional views representing stages inthe articulation of the first jaw as the drive member is moved in alinear motion longitudinally toward a distal end of the end effector andinteracts with the first cam surface in accordance with someembodiments.

FIG. 23A shows the cross-sectional view without the pusher shuttle shownwithin the cartridge in accordance with some embodiments.

FIG. 23B shows the cross-sectional view with the pusher shuttle shownwithin the cartridge in accordance with some embodiments.

FIG. 24A is an illustrative cross-sectional view of a portion of the endeffector of showing the first jaw in an open position and the drivemember in a starting position in accordance with some embodiments.

FIG. 24B is an illustrative cross-sectional view of a portion of theview of FIG. 24A showing a spring used to keep the jaws open prior togripping and clamping operations in accordance with some embodiments.

FIG. 25 is an illustrative cross-sectional view of a portion of the endeffector showing the first jaw and the drive member in grip positions inaccordance with some embodiments.

FIG. 26 is an illustrative cross-sectional view of a portion of the endeffector showing the first jaw and the drive member in a first clamppositions in accordance with some embodiments.

FIG. 27 is an illustrative cross-sectional view of a portion of the endeffector showing the first jaw and the drive member in a staple pushingpositions in accordance with some embodiments.

FIG. 28 is an illustrative cross-sectional view of a portion of the endeffector showing the first jaw and the drive member in a stapler fullyfired position in accordance with some embodiments.

FIG. 29 is an illustrative cross-sectional view of a portion of the endeffector showing the first jaw and the drive member during return of thedrive member to the start position in accordance with some embodiments.

FIG. 30 is an illustrative cross-sectional view of a portion of the endeffector showing the first jaw and the drive member in a completeconfiguration with the drive member back in the to the start position inaccordance with some embodiments.

FIG. 31 is an illustrative drawing showing a lockout mechanism inaccordance with some embodiments.

FIGS. 32A-32B are illustrative drawings showing details of a two degreeof freedom wrist of the end effector with the torque transmittingmechanism in an inline position (FIG. 32A) and in a articulated position(FIG. 32B) in accordance with some embodiments.

DESCRIPTION OF EMBODIMENTS

The following description is presented to enable any person skilled inthe art to create and use a stapler with composite cardan and lead screwdrive for use in a surgical system. Various modifications to theembodiments will be readily apparent to those skilled in the art, andthe generic principles defined herein may be applied to otherembodiments and applications without departing from the spirit and scopeof the inventive subject matter. Moreover, in the following description,numerous details are set forth for the purpose of explanation. However,one of ordinary skill in the art will realize that the inventive subjectmatter might be practiced without the use of these specific details. Inother instances, well-known machine components, processes and datastructures are shown in block diagram form in order not to obscure thedisclosure with unnecessary detail. Identical reference numerals may beused to represent different views of the same item in differentdrawings. Flow diagrams in drawings referenced below are used torepresent processes. A computer system may be configured to perform someof these processes. Modules within flow diagrams representing computerimplemented processes represent the configuration of a computer systemaccording to computer program code to perform the acts described withreference to these modules. Thus, the inventive subject matter is notintended to be limited to the embodiments shown, but is to be accordedthe widest scope consistent with the principles and features disclosedherein.

Referring now to the drawings, in which like reference numeralsrepresent like parts throughout the several views, FIG. 1 is anillustrative plan view of a teleoperated surgical system 10, typicallyused for performing a minimally invasive diagnostic or surgicalprocedure on a Patient 12 who is lying down on an Operating table 14.The system can include a Surgeon's Console 16 for use by a Surgeon 18during the procedure. One or more Assistants 20 may also participate inthe procedure. The teleoperated surgical system 10 can further include aPatient Side Cart 22 and an Electronics Cart 24. The Patient Side Cart22 can manipulate at least one removably coupled tool assembly 26(hereinafter also referred to as a “tool”) through a minimally invasiveincision in the body of the Patient 12 while the Surgeon 18 views thesurgical site through the Console 16. An image of the surgical site canbe obtained by an endoscope 28, such as a stereoscopic endoscope, whichcan be manipulated by the Patient Side Cart 22 to orient the endoscope28. The Electronics Cart 24 can be used to process the images of thesurgical site for subsequent display to the Surgeon 18 through theSurgeon's Console 16. The number of surgical tools 26 used at one timewill generally depend on the diagnostic or surgical procedure and thespace constraints within the operating room among other factors.

FIG. 2 is an illustrative perspective view of the Surgeon's Console 16.The Surgeon's Console 16 includes a left eye display 32 and a right eyedisplay 34 for presenting the Surgeon 18 with a coordinated stereo viewof the surgical site that enables depth perception. The Console 16further includes one or more input control devices 36, which in turncause the Patient Side Cart 22 (shown in FIG. 1) to manipulate one ormore tools. The input control devices 36 can provide the same degrees offreedom as their associated tools 26 (shown in FIG. 1) to provide theSurgeon with telepresence, or the perception that the input controldevices 36 are integral with the tools 26 so that the Surgeon has astrong sense of directly controlling the tools 26. To this end,position, force, and tactile feedback sensors (not shown) may beemployed to transmit position, force, and tactile sensations from thetools 26 back to the Surgeon's hands through the input control devices36.

FIG. 3 is an illustrative perspective view of the Electronics Cart 24.The Electronics Cart 24 can be coupled with the endoscope 28 and caninclude a processor to process captured images for subsequent display,such as to a Surgeon on the Surgeon's Console, or on another suitabledisplay located locally and/or remotely. For example, where astereoscopic endoscope is used, the Electronics Cart 24 can process thecaptured images to present the Surgeon with coordinated stereo images ofthe surgical site. Such coordination can include alignment between theopposing images and can include adjusting the stereo working distance ofthe stereoscopic endoscope.

FIG. 4 is an illustrative bock diagram diagrammatically representingfunctional relationships among components of a teleoperated surgerysystem 50 (such as system 10 of FIG. 1). As discussed above, a Surgeon'sConsole 52 (such as Surgeon's Console 16 in FIG. 1) can be used by aSurgeon to control a Patient Side Cart (Surgical Robot) 54 (such asPatent Side Cart 22 in FIG. 1) during a minimally invasive procedure.The Patient Side Cart 54 can use an imaging device, such as astereoscopic endoscope, to capture images of the procedure site andoutput the captured images to an Electronics Cart 56 (such as theElectronics Cart 24 in FIG. 1). As discussed above, the Electronics Cart56 can process the captured images in a variety of ways prior to anysubsequent display. For example, the Electronics Cart 56 can overlay thecaptured images with a virtual control interface prior to displaying thecombined images to the Surgeon via the Surgeon's Console 52. The PatientSide Cart 54 can output the captured images for processing outside theElectronics Cart 56. For example, the Patient Side Cart 54 can outputthe captured images to a processor 58, which can be used to process thecaptured images. The images can also be processed by a combination theElectronics Cart 56 and the processor 58, which can be coupled togetherto process the captured images jointly, sequentially, and/orcombinations thereof. One or more separate displays 60 can also becoupled with the processor 58 and/or the Electronics Cart 56 for localand/or remote display of images, such as images of the procedure site,or other related images.

FIGS. 5A-5B are illustrative drawings showing a Patient Side Cart 22 anda surgical tool 62, respectively in accordance with some embodiments.The surgical tool 62 is an example of the surgical tools 26. The PatientSide Cart 22 shown provides for the manipulation of three surgical tools26 and an imaging device 28, such as a stereoscopic endoscope used forthe capture of images of the site of the procedure. Manipulation isprovided by teleoperated mechanisms having a number of robotic joints.The imaging device 28 and the surgical tools 26 can be positioned andmanipulated through incisions in the patient so that a kinematic remotecenter is maintained at the incision to minimize the size of theincision. Images of the surgical site can include images of the distalends of the surgical tools 26 when they are positioned within thefield-of-view of the imaging device 28.

FIG. 6 is an illustrative drawing showing an example surgical tool 70that includes a proximal chassis 72, an instrument shaft 74, and adistal end effector 76 having a jaw 78 that can be articulated to grip apatient tissue. The proximal chassis includes input couplers that areconfigured to interface with and be driven by corresponding outputcouplers of the Patient Side Cart 22. The input couplers are drivinglycoupled with drive shafts that are disposed within the instrument shaft74. The drive shafts are drivingly coupled with the end effector 76.

FIG. 7 is perspective view of a portion of a torque transmittingmechanism 102 for transmitting torque through an angle, in accordancewith some embodiments. The torque transmitting mechanism 102 includescardan drive shaft 104 and a cardan driven shaft 106 and a doubleuniversal joint 105, also referred to herein as a cardan joint, inaccordance with some embodiments. A cardan shaft is a shaft that has auniversal joint at one or both ends enabling it to rotate freely when invarying angular relation to another shaft or shafts to which it isjoined. A cardan joint is a universal joint in a shaft that enables theshaft to rotate together with another shaft to which it is joined whenthe two shafts are out of axial alignment. U.S. Pat. No. 8,852,174(filed Nov. 12, 2010) issued to Burbank, which is incorporated herein inits entirety by this reference, discloses prior surgical tolls thatinclude two degree of freedom wrists and double universal joints.

FIG. 8 is an exploded perspective view of the torque transmittingmechanism 102 of FIG. 7. The torque transmitting mechanism 102 includesa drive shaft 104, a driven shaft 106 and a metal coupling member 108disposed between them. The drive shaft 104, the driven shaft 106, orboth drive shaft 104 and driven shaft 106, may comprise metal. The driveshaft 104 includes a proximal end 110 and a distal end 112. The drivenshaft 106 includes a proximal end 114 and a distal end 116. The distalend 112 of the drive shaft 104 includes opposed facing arms 118 withholes 120 that are aligned to define a drive axis clevis 122. Theproximal end 114 of the driven shaft 106 includes opposed facing arms124 with holes 126 that are aligned to define a drive axis clevis 123.

The metal coupling member 108 comprises a generally cylindrical sleevestructure that defines a proximal end opening 127 and a distal endopening 129. A drive shaft plastic bearing 128 having a partiallyspherical outer surface portion 131 is sized to fit within the proximalend opening 127 for smooth partial rotation therein. A driven shaftplastic bearing 130 having a partially spherical outer surface portion133 is sized to fit within the distal end opening 130 for smooth partialrotation therein.

The drive shaft plastic bearing 128 defines a proximal plastic axialengagement structure 132 and the driven shaft plastic bearing 130defines a complementary distal plastic axial engagement structure 134.The proximal plastic axial engagement structure 132 and the distal axialengagement structure 134 have complementary shapes that cooperate duringaxial rotation of the drive shaft 104 and the driven shaft 106 to tiethe relative angular orientation between the drive shaft 104 and thecoupling member 108 to the relative angular orientation between thedriven shaft 106 and the coupling member 108. More particularly, theproximal plastic axial engagement structure 132 and the distal axialengagement structure 134 cooperate to constrain the coupling member 108to be oriented at an equivalent relative angle to both the drive shaft104 and the driven shaft 106, such that any rotational speed differencesbetween the drive shaft 104 and the coupling member 108 are effectivelycanceled when the rotation of the coupling member 108 is transferred tothe driven shaft 106, thereby substantially eliminating rotational speeddifferences between the drive shaft 104 and the driven shaft 106. Atorque transmitting mechanism for transmitting torque through an anglewhile substantially eliminating rotational speed differences between adrive shaft 104 and a driven shaft 106 is commonly referred to as aconstant velocity (CV) joint. In accordance with some embodiments, theproximal plastic axial engagement structure 132 includes a first plasticspherical gear structure and the distal axial engagement structure 134includes a first plastic spherical gear structure.

The first drive shaft plastic bearing 128 defines a proximal transversebore 136 extending through the partially spherical outer surface portion131 transverse to the first plastic engagement structure 132. The firstdrive shaft plastic bearing 128 defines a proximal opening 140 sized topermit passage of the drive axis clevis 122 so as to align holes 120with the proximal transverse bore 136. The first drive shaft plasticbearing 128 defines a proximal transverse slot 138 that extends throughthe partially spherical outer surface portion 131 at a right angle tothe transverse bore 136. The proximal transverse slot 138 extendsthrough a partial circumference of the first drive shaft plastic bearing128 having an axis aligned with an axis of the proximal transverse bore136.

The second drive shaft plastic bearing 130 defines a distal transversebore 142 extending through the partially spherical outer surface portion133 transverse to the second plastic engagement structure 130. Thedriven shaft plastic bearing 130 is secured to a distal hub 135 used tomount to the proximal portion of the end effector (described below). Thedriven shaft plastic bearing 130 is secured to a distal hub 135 define adistal opening 144 sized to permit passage of the driven axis clevis 123so as to align holes 126 with the distal transverse bore 142. The seconddrive shaft plastic bearing 130 defines a distal transverse slot 146that extends through the partially spherical outer surface portion 133at a right angle to the distal transverse bore 146. The distaltransverse slot 146 extends through a partial circumference of thesecond drive shaft plastic bearing 130 having an axis aligned with anaxis of the distal transverse bore 142.

The metal coupling member 108 defines opposed diametrically alignedproximal holes 148 extending through it adjacent its proximal endopening 127. The first drive shaft plastic bearing 128 is insertedwithin the proximal end opening 127, with the proximal end holes 148aligned with the proximal transverse slot 138. A proximal coupling pin150 extends through the aligned proximal end holes 148 and the proximaltransverse slot 138 and is matingly secured to opposed inner surfaces ofthe coupling member 108 to permit rotation of the first drive shaftplastic bearing 128 about an axis of the proximal coupling pin 150. Aproximal cross pin 152 defines a proximal cross pin bore 154 thatextends therethrough. The proximal cross pin 152 extends through theproximal transverse bore 136 and is secured therein to permit rotationof the first drive shaft plastic bearing 128 about the axis of theproximal cross pin 152. The proximal cross pin bore 154 is sized topermit passage of the proximal coupling pin 150, which extends throughit and has opposed ends secured to diametrically opposed sides of themetal coupling member 108. Thus, the proximal coupling pin 150 and theproximal cross pin 152 maintain a perpendicular, cross, relationshipwith each other.

The metal coupling member 108 defines opposed diametrically aligneddistal openings 156 extending through it adjacent its distal end opening129. The second drive shaft plastic bearing 130 is inserted within thedistal end opening 129, with the distal end holes 156 aligned with thedistal transverse slot 146. A distal coupling pin 158 extends throughthe aligned proximal end openings 156 and the proximal transverse slot146 and is matingly secured to opposed inner surfaces of the couplingmember 108 to permit rotation of the second drive shaft plastic bearing130 about an axis of the distal coupling pin 156. A distal cross pin 160defines a distal cross pin bore 162 that extends therethrough. Thedistal cross pin 160 extends through the distal transverse bore 142 andis secured therein to permit rotation of the second drive shaft plasticbearing 130 about an axis of the distal cross pin 160. The distal crosspin bore 162 is sized to permit passage of the distal coupling pin 158,which extends through it and has opposed ends secured to diametricallyopposed sides of the metal coupling member 108. Thus, the distalcoupling pin 158 and the proximal cross pin 160 maintain aperpendicular, cross, relationship with each other.

FIG. 9 is a perspective partially cut away view of the torquetransmitting mechanism of FIGS. 7-8 102 shown as assembled in accordancewith some embodiments. The coupling member 108 is shown partially cutaway to show the drive shaft plastic bearing 128 and the driven shaftplastic bearing 130 that are partially enclosed within it. A portion ofthe drive shaft 104 that is encompassed within the drive shaft plasticbearing 128 is illustrated using dashed lines. Similarly, a portion ofthe driven shaft 106 that is encompassed within the driven shaft plasticbearing 130 is illustrated using dashed lines. FIG. 9 illustrates thetorque transmitting mechanism 102 in an inline configuration in whichthe drive shaft 104 and the driven shaft 106 are longitudinally aligned.

The proximal coupling pin 150, which passes through the proximal crosspin bore 154 formed in the proximal cross pin, is matingly securedwithin the proximal holes 148 formed on diametrically opposed sides ofthe coupling member 108 adjacent to its proximal opening 127. Likewise,the distal coupling pin 158, which passes through the distal cross pinbore 162 formed in the distal cross pin 160, is matingly secured withinthe proximal holes 156 formed on diametrically opposed sides of thecoupling member 108 adjacent to its distal opening 129. Moreover, theproximal cross pin 152 is extends within and is rotatable relative tothe holes 120 formed in the opposed facing arms 118 of the drive axisclevis 122 and extends within and is rotatable relative to the proximaltransverse bore 136. Likewise, the distal cross pin 160 extends withinand is rotatable relative to the holes 126 formed in the opposed facingarms 124 of the driven axis clevis 123 and extends within and isrotatable relative to the distal transverse bore 142.

Accordingly, the proximal cross pin 152 rotates about the drive shaftaxis in unison with the drive shaft 104. Similarly, the driven axisrotates about the driven axis in unison with the distal cross pin 160.

The perpendicular cross mounting of the proximal coupling pin 150 to theproximal cross pin 152 imparts to the coupling pin 150, rotation forcesabout the drive shaft axis that are imparted to the cross pin 152 due torotation of the drive shaft 104. Since the proximal coupling pin 150 andthe distal coupling pin 160 each is matingly secured to the metalcoupling structure 108, a rotational force imparted to the proximalcoupling pin 150 is imparted through the coupling member 108 to thedistal coupling pin 158. Moreover, the perpendicular cross mounting ofthe distal coupling pin 158 to the distal cross pin 160 imparts to thedriven shaft 106, rotation forces about the driven shaft axis that havethe same magnitude as and that are responsive to rotation forcesimparted about the drive shaft axis of the drive shaft 104.

The first drive shaft plastic bearing 128 can move in two degrees offreedom (2-dof). Movement of the first drive shaft plastic bearing 128in a first degree of freedom involves the first drive shaft plasticbearing 128 rotating about the axis of the proximal cross pin 152 withthe proximal coupling pin 150, which is in a fixed position relative tothe coupling member 108, sliding within the proximal transverse slot138. Movement of the first drive shaft plastic bearing 128 in a seconddegree of freedom involves the bearing 128 about the proximal couplingpin 150, which is in a fixed position relative to the coupling member108.

Likewise, the second drive shaft plastic bearing 130 can move in twodegrees of freedom (2-dof). Movement of the second drive shaft plasticbearing 130 in a first degree of freedom involves the second drive shaftplastic bearing 130 rotating about the axis of the distal cross pin 160with the distal coupling pin 158, which is in a fixed position relativeto the coupling member 108, sliding within the distal transverse slot146. Movement of the second drive shaft plastic bearing 130 in a seconddegree of freedom involves the bearing 130 rotating about the distalcoupling pin 158, which is in a fixed position relative to the couplingmember 108.

FIG. 10A is illustrative cross-sectional view of the torque transmittingmechanism 102 of FIGS. 7-9 showing details of a drive shaft plasticbearing 128 outer spherical surface 131 interfacing with a first innerspherical surface 172 of the coupling member 108, and also showingdetails of the driven shaft plastic bearing 130 outer spherical surface133 interfacing with a second inner spherical surface 174 of thecoupling member 108. An advantage of using an outer spherical surfacefor plastic bearings is lower cost and accuracy of the components, sincegear surfaces can be difficult to manufacture accurately from metal,which makes them very costly. With injection molding a more repeatablyaccurate part can be produced with much lower cost. Moreover, theplastic also can provide some lubrication. As discussed above, theconstraint provided by the first coupling pin 150 axially androtationally couples the drive shaft 104 and the drive shaft plasticbearing 128 mounted thereon, to the coupling member 108, and theconstraint provided by the second coupling pin 158 axially androtationally couples the driven shaft 106 and the driven shaft plasticbearing 130 mounted thereon to the coupling member 108. Additionally,the constraint provided by the interfacing spherical surfaces canfurther constrain the drive shaft 104 and the driven shaft 106 relativeto the coupling member 108.

FIG. 10B is an illustrative cross-sectional view of the torquetransmitting mechanism 102 of FIGS. 7-10A, illustrating engagementbetween gear teeth 176 drive shaft plastic bearing 128 and gear teeth178 of the driven shaft plastic bearing 130 for an angled configuration,in accordance with some embodiments. The cross-section illustratedincludes the drive axis 164, the driven axis 168, and the couplingmember axis 166, and is taken along a view direction parallel to theaxes of the first coupling pin 150 and the second coupling pin 158.

In the angled configuration illustrated in FIG. 10B, the driven axis ofthe driven shaft 106 deviates from the drive axis of the drive shaft 104by 70 degrees. The constraint provided by engagement between the driveshaft gear teeth 176 of the drive shaft plastic bearing 128 and the gearteeth 178 of the driven shaft plastic bearing 130 results in the 70degrees being equally distributed amongst a 35 degree deviation betweenthe drive axis 164 and the coupling axis 166, and a 35 degree deviationbetween the coupling axis 166 and the driven axis 168. By constrainingthe coupling member 108 to be oriented at an equivalent relative angleto both the drive shaft 104 and the driven shaft 106, any rotationalspeed differences between the drive shaft and the coupling member areeffectively canceled when the rotation of the coupling member 108 istransferred to the driven shaft 106, thereby substantially eliminatingany rotational speed differences between the drive shaft 104 and thedriven shaft 106.

In some embodiments, the gear teeth 176 of the drive shaft plasticbearing 128 and the gear teeth 178 of the driven shaft plastic bearing130 are spherically oriented so as to provide the above describedconstraint between the drive shaft 104 and the driven shaft 106 for anyangular orientation of the torque transmitting mechanism 102. For anangled configuration, rotation of the drive shaft 104 and acorresponding rotation of the driven shaft 106 causes different portionsof the gear teeth 176 of the drive shaft plastic bearing 128 and thegear teeth 178 of the driven shaft plastic bearing 130 to be intersectedby the coupling axis 108. The use of spherical gear teeth allows thismovement of the shafts while still providing the angular constraintnecessary to orient the coupling member relative to the drive shafts.

FIG. 11 is an illustrative cross-sectional view of the torquetransmitting mechanism 102 of FIGS. 7-10B, illustrating theconfiguration of the proximal transverse slot 138 and the similar distaltransverse slot 146, in accordance with many embodiments. The proximaltransverse slot 138 is configured to accommodate the first coupling pin150 throughout a range of angles between a drive axis 164 and a couplingaxis 166. Likewise, the distal transverse slot 146 is configured toaccommodate the second coupling pin 158 throughout a range of anglesbetween the driven axis 168 and the coupling axis 166. When the torquetransmitting mechanism 102 is operated in an angled configuration, theposition of the first coupling pin 150 within the proximal transverseslot 138 will undergo a single oscillation cycle for each 360 degreerotation of the drive shaft 104. Likewise, the position of the secondcoupling pin 158 within the distal transverse slot 146 will undergo asingle oscillation cycle for each 360 degree rotation of the drivenshaft 106.

The oscillation of the metal coupling pins 150, 158 within thetransverse slots 138, 146 can be described with reference to FIGS.12A-12B. FIG. 12A is an illustrative side elevation view of the torquetransmitting mechanism 102 along a view direction normal to the axes ofthe coupling pins 150, 158. FIG. 12B is an illustrative side elevationview of torque transmitting mechanism 102 along a view directionparallel to the axes of metal coupling pins 150, 158. In FIGS. 12A-12B,the coupling member 108 is transparent and indicated with dashed linesto illustrate interactions between mechanism components. In the positionshown in FIG. 12A, to accommodate the angle between the drive shaft 104and the coupling member 108, the first coupling pin 150 is canted withinthe proximal transverse slot 138 (this can be visualized by consideringthe slot shape illustrated in FIG. 11 in conjunction with the shaftangles illustrated in FIG. 12A). In FIG. 12B, the coupling member 108has an angular orientation that is 90 degrees from the coupling memberorientation of FIG. 12A, thereby aligning the metal coupling pins 150,158 with the view direction. For the orientation shown in FIG. 12B, themetal coupling pins 150, 158 are not canted within the respectiveproximal and distal transverse slots 138, 146 (similar to FIG. 11).During a 360 degree revolution of the torque transmitting mechanism 102,the position of the metal coupling pins 150, 158 within the respectiveproximal and distal transverse slots 138, 146 will complete anoscillation cycle. As explained above, advantages of using plasticinclude reduced cost and repeatability of manufacturing. In addition,plastic can provide an interface having less friction. Furthermore,plastic can be more forgiving than metal if there is some small amountof interference. The use of plastic also could eliminate the need forlubrication.

FIG. 13 is an illustrative drawing shows a portion of the torquetransmitting mechanism 102 with the coupling member 108 removed and a“see through” driven shaft plastic bearing 130 to better illustrate thecross mounting of the distal coupling pin 158 to the distal cross pin160. The distal metal cross pin 160 is received within the distaltransverse bore 142 of the driven shaft plastic bearing 130 and isrotatable within the distal transverse bore 142. The distal coupling pin158 is received within the distal cross pin bore 162 of the distal metalcross pin 160. Relative rotation between the driven shaft 106 and thecoupling member 108 about the centerline of the coupling pin 400 occursvia rotation of the distal coupling pin 158 relative to the couplingmember 108 and/or rotation of the distal coupling pin 158 relative tothe driven shaft metal cross pin 160 and within the distal transverseslot 146. Similarly, the proximal metal cross pin 152 is received withinthe proximal cross pin bore 136 of the drive shaft plastic bearing 128and it is rotatable within the proximal transverse bore 136. Theproximal coupling pin 150 is received within proximal cross pin bore 154of the proximal metal cross pin 152. Relative rotation between the driveshaft 104 and the coupling member 108 about the centerline of theproximal coupling pin 150 occurs via rotation of the proximal couplingpin 150 relative to the coupling member 108 and/or rotation of thecoupling pin 150 relative to the proximal cross pin 152 and within theproximal transverse slot 138. It will be appreciated that rotationalload forces imparted during operation due to changes in shaftmisalignment of the drive shaft 104 and the driven shaft 106advantageously are supported using the metal coupling pins 150, 158 andmetal cross pins 152, 160. Thus, the spherical surfaces of the plasticbearing components 128, 130 are not exposed to rotational load forcesimparted due to misalignment of the drive shaft 104 and the driven shaft106.

FIG. 14A is an illustrative perspective view showing details of theproximal and distal cross pin bores 136, 142 of the respective driveshaft plastic bearing 128 and driven shaft plastic bearing 130 inaccordance with some embodiments. FIG. 14B is an illustrativeperspective view showing details of the proximal transverse slot 138 andthe distal transverse slot 146 of the respective drive shaft plasticbearing 128 and driven shaft plastic bearing 130 in accordance with someembodiments. In accordance with some embodiments, high-strength materialis used to produce components that are subject to load forces imparteddue to misalignment of the drive shaft 104 and the driven shaft 106during use. The high strength materials include metal, such as steel orstainless steel, of an appropriate type and strength for the expectedloading. The high strength components can be machined or MIM. Materialsfor ‘plastic’ can be PPA with Glass or Carbon, PEI (Ultem) with Glass orCarbon, PEEK with glass or carbon fill, PPSU (Radel) with Glass orCarbon fill, for example. The plastics could also have silicone or PTFEfiller to help with lubricity. The plastic parts can be injectionmolded. During assembly, the plastic parts slip over the metal pins andare trapped within the larger diameter pins. The option to MIM the metalcomponents and injection mold the spherical interface components canmakes for an affordable option for a cardan in for single patient usedevices. The plastic portion can be self-lubricating and reduce frictionat the rotation interfaces. A possible tradeoff is strength at thespherical interface.

FIG. 15 is an illustrative perspective drawing, with a partial cutaway,of a surgical tool assembly 200 in accordance with some embodiments. Thetool assembly 200 includes a proximal actuation assembly 202, a mainshaft 206, a two degree of freedom (2-dof) wrist 208, shown in partialcutaway, and an end effector 210. The end effector 210 includes a firstarticulable jaw 214 rotatably secured to a base 212, a stationary secondjaw 216 detachably secured to the base 212 and a 2-dof wrist 208operatively coupled between the main shaft 206 and the base 212. The endeffector base 212 includes a pivot member 217 about which a proximal endof the first jaw 214 pivots to achieve opening and closing movement ofthe first jaw 214 relative to the second jaw 216. In some embodiments,the pivot member includes a pivot pin 217 that defines a pivot axis 213about which the first jaw 214 pivots and that is secured between the endeffector base 212 and a proximal end of the first jaw 214. A proximalend of the first jaw 214 pivots about the pivot axis 213 to achieveopening and closing movement of the first jaw 214 relative to the secondjaw 216. In some embodiments, the actuation assembly 202 is operativelycoupled with the wrist 208 so as to selectively reorient the endeffector 210 relative to the main shaft 206 in two dimensions, and isoperatively coupled with the end effector 210 so as to actuate one ormore end effector features, such as the first articulable jaw 214,relative to the end effector base 212. A variety of actuation componentscan be used to couple the actuation assembly 202 with the wrist 208 andwith the end effector 210, for example, control cables, cable/hypotubecombinations, drive shafts, pull rods, and push rods. In manyembodiments, the actuation components are routed between the actuationassembly 202 and the wrist 208 and the end effector 210 through a boreof the main shaft 206. The end effector 210 shown in FIG. 15 includes asurgical stapler in which the second detachable stationary second jaw216 includes an elongated stapler cartridge 218, and in which anarticulable first jaw 214 includes an anvil 220 against which staplesare deformed to staple together tissue disposed between the first andsecond jaws 214, 216.

FIG. 16 is an illustrative perspective view, with a partial cutaway, ofthe end effector 210 of FIG. 15 with an empty second jaw 216 from whichthe stapler cartridge is removed. More particularly, the empty secondjaw 216 includes a stapler cartridge support channel structure 221 thatincludes sidewalls 225 and an outer facing bottom wall 224 that aresized to receive the stapler cartridge 218. As explained below, thesupport channel bottom wall 224, which acts as a second jaw cam surface,defines a central second longitudinal cam slot 255 that runs most of thelength of the bottom wall 224. An elongated rotary drive screw 222,which includes a distal end 222-2 and a proximal end 222-1, extendslongitudinally along the length of the second jaw 216. The proximal endof the drive screw 222 is rotatably supported within the end effectorbase 212. The distal end 222-2 of the drive screw 222 is received withinand rotatably supported by an annular bearing 228, which is secured toan upstanding base 230 such that the drive screw runs down the center ofthe support channel 221 between the upstanding walls 222 and above thebottom wall 224.

FIG. 17 is an illustrative exploded view of a detachable stationarysecond jaw 216 in accordance with some embodiments. The second jaw 216includes the support channel structure 221, which includes a proximalend 221-1 and a distal end 221-2. The support channel 221 includes thesidewalls 225 and the bottom wall 224, which defines the secondelongated longitudinal slot 232, only a small distal portion of which isvisible. The elongated cartridge 218 includes a proximal end 218-1 and adistal end 218-2. The cartridge includes cartridge outer sidewalls 234and an upper surface 236. The upper surface 236 faces the anvil 220 ofthe first jaw, which acts as an anvil, when the second jaw is mounted tothe end effector base 212. The upper surface 236 of the cartridge 218defines a central first longitudinal cartridge slot 238 that extendsthrough the cartridge 218 and that is aligned with the secondlongitudinal cam slot 255 when the cartridge 218 is disposed within thesupport channel structure 221. The cartridge upper surface portionincludes inner opposed facing sidewalls 238-1, 238-2 that define thecartridge slot 238 and act as a cam surfaces to guide a drive member250, as described more fully below. The upper surface 236 also definesmultiple rows of longitudinally spaced staple retention slots 240 thatextend longitudinally along one side of the first cartridge slot 238 anddefines multiple rows of longitudinally spaced staple retention slots240 that extend longitudinally along an opposite side of the firstcartridge slot 238. Each staple retention slot 240 is sized to receive afastener 242 and a staple pusher 244. A pusher shuttle 246 includes aplurality of inclined upstanding cam wedges 246 and a knife edge 248upstanding between and proximal to the cam wedges 246. The cartridge 218defines multiple longitudinal slots (not shown) in its underside alongwhich the cam wedges 246 can slide with the knife upstanding from andsliding within the first cartridge slot 238. Alternatively, inaccordance with some embodiments, a knife (not shown) can be secured tothe drive member 250 described below.

During operation of surgical stapler end effector 210, pusher shuttle246 translates through the longitudinal pusher slots 239-1, 239-2,formed in an underside of the cartridge 218 to advance the cam wedges246 into sequential contact with pushers 244 within the longitudinallyspaced retention slots 240, to cause pushers 244 to translate verticallywithin retention slots 240, and to urge fasteners 242 from retentionslots 240 into the staple deforming cavities (not shown) formed withinthe anvil 220 of the first jaw 214. As the pusher shuttle 246 translateslongitudinally, it pushes up fasteners 242, which are deformationagainst the anvil 220. Meanwhile, the knife edge 248 upstands throughthe first cartridge slot 238 and cuts tissue between tissue regionsstapled through action of the cam wedges 246, fasteners 242 and theanvil 220. U.S. Pat. No. 8,991,678 (filed Oct. 26, 2012) issued toWellman et al., which is incorporated herein in its entirety by thisreference, discloses a surgical stapler cartridge and its operation.

FIG. 18 is an illustrative cross sectional view of the end effector 210of FIGS. 15-17 in accordance with some embodiments. Like the view inFIG. 16, the cartridge 218 is removed leaving the second jaw 216 asprimarily consisting of the empty support channel structure 221. Themain shaft 206 encloses the distal drive shaft 104, which extendsthrough the center of the main shaft 206 between the proximal actuationassembly 202 and the drive shaft plastic bearing 128. The proximaldriven shaft 106 extends between the driven shaft plastic bearing 130and the proximal end 222-1 of the rotary drive screw 222. Referring backto FIGS. 7-8, it can be seen that a distal end 116 of the driven shaft106 defines a female coupler 223 contoured to interfit with acomplementary male coupler 227 at the distal end 222-2 of the drivescrew so that the driven shaft 106 and the rotary drive screw 222 rotatein unison. The driven shaft 106 houses additional control componentssuch as steering (hypo)tubes which are not shown in order to simplifythe drawings. A screw driven drive member 250 is mounted to the endeffector 210 between the first jaw and the second jaw. The drive member250 defines a threaded bore through which the drive screw 222 isthreaded. The drive member 250 is configured so that rotation of thedrive screw in a first rotational direction within the threaded borecauses the drive member 250 to move in a longitudinal path defined bythe rotary drive screw 222 in a direction in toward the drive screwdistal end distal end 222-2. Conversely, rotation of the rotary drivescrew 222 in a second rotational direction within the threaded bore,opposite to the first rotational direction, causes the drive member 250to move in a longitudinal path defined by the drive screw 222 in adirection in toward the drive screw proximal end distal end 222-1.

The first jaw 214 includes the anvil 220, an outer top cover 251 thatoverlays a back side of the anvil 220. A first cam surface 249, whichincludes a longitudinally extending first jaw rotation cam surface 259and a longitudinally extending first jaw clamping cam surface 252, isdisposed between the external cover 251 and the anvil 220. The first camsurface is described more fully with reference to FIG. 19B and FIGS.22A-22F. The second jaw 216 defines a longitudinally extending secondcam surface 254. The first jaw rotation cam surface 259 cooperates withthe driver member 250, which acts as a cam follower driven by the screwdrive 222, to rotate the articulable first jaw 214 between open andclosed positions. As explained below with reference to FIG. 24B, aspring is used to keep the jaws open prior to gripping and clamping.With the first jaw 214 in the closed position, the first jaw clampingcam surface 252 and second cam surface 254 are longitudinally alignedand can cooperate with the driver member 250, which acts as a camfollower driven by the screw drive 222, to securely hold anatomicaltissue between the first and second jaws 214, 216 to achieve tissuegripping and tissue clamping.

FIG. 19A is a top elevation view of the first cam surface 249 inaccordance with some embodiments. FIG. 19B is a cross-section viewshowing edges of one side of the first cam surface 249 in accordancewith some embodiments. As explained above, the first cam surface 249 issecurely mounted within the first jaw 214 between the anvil 220, and theexternal top cover 251. The first cam surface 249 includes a proximalend 249-1 and a distal end 249-2 having multiple functional segmentsbetween them: a rotation cam segment 259, a clamping cam segment 252, adistal cross-segment 273, a proximal bridging segment 274 and a proximalbase segment 275.

The rotation cam segment 259 comprises a first elongated cam edge 259-1and a parallel second elongated edge portion 259-2 (also referred toherein as a third pair of lateral side edges 259-1, 259-2), which arelaterally spaced apart and which act as a proximal portion of the firstcam surface 249. A first jaw clamping cam segment 252 comprises a thirdelongated cam edge 252-1 and a parallel fourth elongated cam edge 252-2(also referred to herein as a first pair of lateral side edges 252-1,252-2), which acts as a distal cam portion of the first cam surface 249.The first and third elongated cam edges 259-1, 252-1 are joinedintegrally so as to together define a first continuous edge. The secondand fourth elongated cam edges 259-2, 252-2 are joined integrally so asto together define a second continuous edge. The first continuous edgecomprising cam edges 259-1, 252-1 and the second continuous edgecomprising cam edges 259-2, 252-2 together define a first elongated camfollower slot 253 between them. The first and third cam edges 259-1,252-1 and the second and fourth cam edges 259-2, 252-2 are offset at anangle from each other.

The distal cross-segment 273 connects the distal ends of the third andfourth edges 252-1, 252-2 and is secured to a distal portion of the topcover 251. The proximal base segment 275 includes parallel edges 275-1,275-2 that are upstand substantially transverse to the third and fourthcam edges 252-1, 252-2 and that are secured to a proximal end portion ofthe top cover 251. The proximal bridging segment 274 includes paralleledges 274-1, 274-2 that respectively integrally interconnect the firstcam edge 259-1 with one of the base edges 275-1 and interconnect thesecond cam edge 259-2 with the other of the base edges 275-1.

FIG. 20 is an illustrative bottom elevation view of the longitudinallyextending second cam surface 254 in accordance with some embodiments.The second cam surface 254 is formed in the bottom wall 224 of thestapler cartridge support channel structure 221. The second cam surface254 includes fifth and sixth elongated cam edges 254-1, 254-2 (alsoreferred to as a second pair of lateral side edges 254-1, 254-2), whichare laterally spaced apart. The fifth and sixth elongated cam edges254-1, 254-2 together define the second elongated cam follower slot 255between them. Proximal and distal cross members 278-1 and 278-2interconnect the fifth and sixth edges portions.

FIG. 21 is an illustrative perspective view of the drive member 250 inaccordance with some embodiments. The drive member 250 has an I-beamcontour that includes a cross-beam portion 258, a first transverse beamportion 260 secured to a first end of the cross-beam portion 258, and asecond transverse beam 262 secured to a second end of the cross-beam 258portion. The cross-beam portion 258 defines a threaded bore 261 thatextends through it that is sized and contoured to engage a drive screw(not shown). The first and second transverse beam portions 260, 262extend from the cross-beam 258 in a direction perpendicular to an axisof the threaded bore 261. In operation, the cross-beam portion 258 actsas a cartridge slot cam follower. The cross-beam portion 258 is sized toslidably fit simultaneously within the first cam follower slot 253 andthe second elongated cam follower slot 255. The first transverse beamportion 260 defines a first inward facing surface 260-1 that acts as afirst jaw cam follower. The second transverse beam 262 defines a secondinward facing surface 260-2 that acts as a second jaw cam follower.

FIGS. 22A-22F are schematic cross-sectional side views representingstages in the articulation of the first jaw 214 as the drive member 250is moved in a linear motion longitudinally from a proximal startingposition toward a distal end of the end effector 210 and interacts withthe rotation cam 259 (also referred to herein as the third pair oflateral side edges 259-1, 259-2) and the first jaw clamping cam 252(also referred to herein as the first pair of lateral side edges 252-1,252-2 of the first cam surface 249 along the way, in accordance withsome embodiments. Certain components of the end effector 210 are omittedto simplify the drawings. Moreover, in this cross-section side view,only the second side edges 259-2, the fourth cam edge 252-2, oneparallel edge 274-2 and one base edge 275-2 are shown. In thisdescription, the linear position of the drive member 250 is expressed interms of an X_(N) positions along an X axis collinear with the axis ofthe drive screw 222. A fastener 282 secures the first cam surface 249 tothe first arm 214 (indicated by dashed lines). The first arm 214 ismounted to a pivot pin 217 secured to the end effector base 212 (notshown) so as to be rotatable about an axis of the pivot pin 217 relativeto the base 212 and to the second jaw 216 (not shown), which is attachedto the base 212 during operation. The drive member 250 is mounted uponthe drive screw 222. As most clearly shown in FIGS. 16-17, the drivescrew 222 extends longitudinally (along the X axis) within the cartridgesupport channel structure 221 for substantially its entire length. Inoperation, the drive screw 222 rotatably extends through a longitudinalcavity (not shown) formed within the cartridge 218 beneath the rows ofretention slots 240. Forward rotation of the drive screw 222 causes thedrive member 250 to move linearly along the drive screw toward the drivescrew distal end 222-1, which is disposed near a distal end of thesecond jaw 216.

FIG. 22A shows the first arm 214 fully open inclined at an angle of 60degrees relative to a longitudinal axis of the second jaw 216 and withthe drive member 250 located at starting linear position X₁. It will beappreciated that different stated angles and different X_(N) positionsare approximations and examples used for illustrative purposes. Morespecifically, the drive member 250 is disposed with its cross-beamportion 258 between the parallel edges 274-1, 274-2 of the bridgingsegment 274 and with its first transverse beam portion 260 spaced apartin a proximal direction from the first and second cam edges (the thirdpair of lateral side edges) 259-1, 259-2 of the rotation cam 259.

FIG. 22B shows the first arm 214 partially open inclined at an angle of52 degrees relative to the longitudinal axis of the second jaw 216 andwith the drive member 250 located at linear position X₂. The drivemember 250 is disposed with its cross-beam portion 258 partially betweenthe a portion of the parallel first and second cam edges (the third pairof lateral side edges 259-1, 259-2) and between a portion of theparallel edges 274-1, 274-2 of the bridging segment 274 and with itsfirst transverse beam portion 260 interacting as a cam follower with thefirst and second cam edges 259-1, 259-2 of the rotation cam 259. Theinteraction between the first transverse beam portion 260 first andsecond cam edges 259-1, 259-2 during linear x-direction motion of thedrive member 250 from X₁ to X₂ has caused the first arm 214 to rotatefrom a 60 degree angle to a 52 degree angle.

FIG. 22C shows the first arm 214 partially open inclined at an angle of45 degrees relative to the longitudinal axis of the second jaw 216 andwith the drive member 250 located at linear position X₃. The drivemembers 250 is disposed with its cross-beam portion 258 fully betweenthe parallel first and second cam edges (the third pair of lateral sideedges) 259-1, 259-2 of the rotation cam and with its first transversebeam portion 260 interacting as a cam follower with the first and secondcam edges 259-1, 259-2 of the rotation cam 259. The interaction betweenthe first transverse beam portion 260 first and second cam edges 259-1,259-2 during linear x-direction motion of the drive member 250 from X₂to X₃ has caused the first arm 214 to rotate from a 52 degree angle to a45 degree angle.

FIG. 22D shows the first arm 214 partially open inclined at an angle of20 degrees relative to the longitudinal axis of the second jaw 216 andwith the drive member 250 located at linear position X₄. The drivemembers 250 is disposed with its cross-beam portion 258 fully betweenthe parallel first and second cam edges (the third pair of lateral sideedges) 259-1, 259-2 of the rotation cam and with its first transversebeam portion 260 interacting as a cam follower with the first and secondcam edges 259-1, 259-2 of the rotation cam 259. The interaction betweenthe first transverse beam portion 260 first and second cam edges 259-1,259-2 during linear x-direction movement of the drive member 250 from X₃to X₄ has caused the first arm 214 to rotate from a 45 degree angle to a20 degree angle.

FIG. 22E shows the first arm 214 closed inclined at an angle of 0degrees relative to the longitudinal axis of the second jaw 216 and withthe drive member 250 located at linear position X₅. The drive members250 is disposed with its cross-beam portion 258 still fully between theparallel first and second cam edges (the third pair of lateral sideedges) 259-1, 259-2 of the rotation cam but with its first transversebeam portion 260 now interacting as a cam follower with the third andfourth cam edges (the first pair of lateral side edges) 252-1, 252-2 ofthe first jaw clamping cam 252. The interaction between the firsttransverse beam portion 260 first and second cam edges 259-1, 259-2during linear x-direction movement of drive member 250 from X₄ to X₅ hascaused the first arm 214 to rotate from a 20 degree angle to a 0 degreeangle.

In accordance with some embodiments, the first cam surface 249 isconfigured such that the first transverse beam portion 260 transitionsfrom interacting with the first and second cam edges (the third pair oflateral side edges) 259-1, 259-2 of the rotation cam to interacting withthe third and fourth cam edges (the first pair of lateral side edges)252-1, 252-2 of the first jaw clamping cam 252 as the linear motion ofthe drive member 250 causes the first arm 214 to reach a 0 degree angle,parallel with the second jaw 216. In accordance with some embodiments,there is a prescribed spacing that the I-beam maintains between theanvil and cartridge. The distance may be adjusted based upon bycartridge size (e.g., staple length). To achieve this each reload sizehas a different overall height to make the appropriate gape betweenanvil and cartridge. The I-beam is sized and dimensioned to maintainthis distance.

FIG. 22F shows the first arm 214 closed inclined at an angle of 0degrees relative to the longitudinal axis of the second jaw 216 and withthe drive member 250 located at linear position X₆. The drive members250 is disposed with its cross-beam portion 258 fully between theparallel the third and fourth cam edges (the first pair of lateral sideedges) 252-1, 252-2 of the first jaw clamping cam 252 and with its firsttransverse beam portion 260 interacting with the third and fourth camedges 252-1, 252-2 of the first jaw clamping cam 252. The linear motionof the drive member 250 from X₅ to X₆ has caused the first arm 214 butthe rotational angle of the first arm 214 has remained at 0 degreeangle, parallel to the second arm 216.

FIGS. 23A-23B are schematic cross sectional views of the first andsecond jaws in a closed position in a proximal direction along the drivescrew axis in accordance with some embodiments. FIG. 23A shows thecross-sectional view without the pusher shuttle 244 shown within thecartridge 218. FIG. 23B shows the cross-sectional view with the pushershuttle 244 shown within the cartridge 218. Certain components of thejaws 214, 216 are omitted to simplify the drawings.

FIG. 23A shows the drive member 250 disposed so that the first inwardfacing surface 260-1 of the first transverse beam 260 urges therespective third and fourth cam edges 252-1, 252-2 toward the fifth andsixth cam edges 254-1, 254-2 and so that conversely, the second inwardfacing surface 262-1 of the second transverse beam 262 urges therespective fifth and sixth cam edges 254-1, 254-2 toward the third andfourth cam edges 252-1, 252-2. The cam follower surfaces 258-1 ofcross-beam portion 258 interact with opposed cartridge inner sidewallcam surfaces 238-1, 238-2 of the cartridge slot 238 to guide the drivemember 250 along the length of the cartridge 218. The cartridge outersidewalls 234 and the cartridge inner sidewalls 234 define first andsecond elongated pusher channels 239-1, 239-2 that are laterally spacedapart on opposite sides of the cartridge slot 238 and that extendsubstantially along the length of the cartridge 218.

FIG. 23B shows the illustrative cross-section distal end view of FIG.23B with the addition of the pusher shuttle 244 disposed within thepusher channels 239-1, 239-2. The drive member 250 drives the pushershuttle 244 in front of it in a longitudinal direction from a proximalend toward distal ends of the cartridge 218 that is mounted within thesecond jaw 216. It is noted that there is a gap 288 between the anvilsurface 220 and the cartridge 218 in which tissue can be captured.

FIGS. 24A-30 are illustrative cross-sectional drawings of a portion ofthe end effector 210 of FIGS. 15-18 showing the longitudinal movement ofthe drive member 250 and corresponding motion of the first and secondjaws 214, 216 in response to rotation of the rotatable screw drive 222in accordance with some embodiments. As shown in FIG. 15, thearticulable first jaw 214 is pivotally mounted on first and second pivotpins 217 (only one shown) to allow it its proximal end to pivot so as torotatably move its anvil surface 220 toward or way from the cartridge218 disposed within the cartridge support channel structure 221 of thesecond detachable jaw 216. It is noted that the pivot pins are notvisible in the illustrative drawings of FIGS. 24A-30.

FIG. 24A is an illustrative cross-sectional view of a portion of the endeffector 210 of showing the first jaw 214 in an open position and thedrive member 250 in a starting position in accordance with someembodiments. The view in FIG. 24A corresponds to the schematic viewshown in FIG. 22A. FIG. 24B is an illustrative cross-sectional view of aportion of the view of FIG. 24A, enlarged to show a spring 291 seated ina recess disposed to urge the first jaw 214 away from the second jaw 216to keep the jaws in an open position open prior to gripping and clampingoperations in accordance with some embodiments. With the first jaw 214is in an open position, a surgeon can maneuver the end effector 210 soas to position it to encompass anatomical tissue structures that is tobe stapled between the first and second jaws 214, 216. An open first jaw214 is the default position in accordance with some embodiments. Thedrive member 250 is disposed in a starting position adjacent proximalends of the first and second jaws 214, 216 and adjacent the proximal end222-1 of the screw drive 222. The drive member 250 is longitudinallyspaced apart from the pusher shuttle 244 with the pusher shuttle 244positioned at a more distal location within the cartridge 218. The drivemember first transverse beam 260 is disengaged from both the rotationcam surface 259 and from the first jaw clamping cam surface 252 firstjaw flat cam surface 252. It will be appreciated that in thesecross-section views, only portions of the second rotation cam edge 259-2and a portion of the fourth clamping cam edge 252-2 are shown.

With the detachable second jaw 216 is attached, a male coupler 227formed at the proximal end 222-1 of the rotatable screw drive 222, isinserted into and engages the female coupler 223 located at the distalend 116 of the driven shaft 106. It will be appreciated that a rotationforce can be applied to the drive shaft 104, which is mounted within themain shaft 206, and that rotational force is transferred through thetorque transmitting mechanism 102 to the driven shaft 106, which ismounted within the end effector 210, and that force also can betransferred to the drives the screw drive 222, which extendslongitudinally within the cartridge 218 mounted in the second jaw.Hypotubes 290 that can be used to achieve two degree of freedom movementof the end effector 210 also are shown housed within the main shaft.

FIG. 25 is an illustrative cross-sectional view of a portion of the endeffector 210 showing the first jaw 214 and the drive member 250 in grippositions in accordance with some embodiments. The view in FIG. 25corresponds to the schematic view shown in FIG. 22E. FIGS. 22B-22Eillustrate the transition of the first jaw 214 between the startingposition shown in FIG. 24A and the grip position in FIG. 25. During thetransition, the screw drive 222 drives the drive member 250 to advancedistally longitudinally along the axis of the screw drive 222 so thatthe first transverse beam 260 interacts with the second rotation camedge 259-2 to cause the first arm to rotate from the start position tothe grip position. The pusher shuttle 244 defines a bore through whichthe screw drive 222 passes without affecting its longitudinal position.

In the grip position, the drive member 250 is disposed longitudinallyspaced apart from the pusher shuttle 244 with the pusher shuttle 244positioned at a more distal location within the cartridge 218. Thus, thedrive member 250 has not yet caused movement of the pusher shuttle 244and no staples have been discharged. The first transverse beam 260 isengaged with the fourth clamping cam edge 252-2 and the secondtransverse beam 262 is engaged with the sixth clamping edge 254-2. Thefirst and second transverse beams 260, 262, thereby cooperate to exertinward force on the second and fourth clamping edges 252-2, 254-2 so asto urge the first and second jaws 214, 216 into a closed position thatallows a sufficient gap between them accommodate tissue gripped betweenthem.

Once the first jaw 214 is in the grip position, a surgeon then may takesome time to assess whether or not to staple the tissue captured withinthe jaws. In accordance with some embodiments, the surgeon canselectively actuate the screw drive 222 to move the driver member 250back to the starting position to re-open the jaws and maneuver the jawsto capture a different portion of tissue. Thus, a surgeon canselectively grip and release tissue portions in search for the optimaltissue site that he wants to have between gripped between the jaws forinsertion of staples.

FIG. 26 is an illustrative cross-sectional view of a portion of the endeffector 210 showing the first jaw 214 and the drive member 250 in afirst clamp positions in accordance with some embodiments. The view inFIG. 26 corresponds generally to the schematic view shown in FIG. 22F.During a transition from the grip position to the first clamp position,the screw drive 222 drives the drive member 250 to advance distallylongitudinally along the axis of the screw drive 222 to a position thatis longitudinally closer to the pusher shuttle 244 but that does not incontact with the pusher shuttle 244. Thus, no staples are pushed by thepusher shuttle 244 in response to the transition from the grip positionto the first clamp position. In the first clamp position, like the gripposition, the first and second transverse beams 260, 262 cooperate toexert inward force on the second and fourth clamping edges 252-2, 254-2so as to urge the first and second jaws 214, 216 into a closed positionthat allows a sufficient gap between them accommodate tissue grippedbetween them. In accordance with some embodiments, tissue pressureimparted by the jaws can be determined indirectly based upon systemtorque on the lead screw. This can be determined during grip or duringclamp.

FIG. 27 is an illustrative cross-sectional view of a portion of the endeffector 210 showing the first jaw 214 and the drive member 250 in astaple pushing positions in accordance with some embodiments. The viewin FIG. 27 also corresponds generally to the schematic view shown inFIG. 22F. During a transition from the first clamp position to the tothe staple pushing position, the screw drive 222 drives the drive member250 to advance distally longitudinally along the axis of the screw drive222 to a position in which it abuts against and imparts motion to thepusher shuttle 244 causing the pusher shuttle 244 to push staplesthrough tissue and to cause their deformation against the anvil 202 asdescribed above with reference to FIG. 17. In the staple pushingposition, the first and second transverse beams 260, 262 cooperate toexert inward force on the second and fourth clamping edges 252-2, 254-2so as to urge the first and second jaws 214, 216 into a closed positionthat allows a sufficient gap between them accommodate tissue grippedbetween them. It will be appreciated, therefore, that the pushingposition constitutes a second clamping position similar to the firstclamping position.

FIG. 28 is an illustrative cross-sectional view of a portion of the endeffector 210 showing the first jaw 214 and the drive member 250 in astapler fully fired position in accordance with some embodiments. Thepusher shuttle 244 abuts against the upstanding base 230 supporting theannular bearing 228 in which a distal end 222-2 of the drive screw 222rotates. During a transition from the staple pushing position of FIG. 27to the to the stapler fully fired position of FIG. 28, the screw drive222 drives the drive member 250 and the pusher shuttle 244, which abutsagainst it, to traverse distally longitudinally along the entireremaining axis of the screw drive 222 causing the pusher shuttle 244 topush staples through tissue and to cause their deformation against theanvil 202 during the traversal. During the traversal, the first andsecond transverse beams 260, 262 cooperate to exert inward force on thesecond and fourth clamping edges 252-2, 254-2 as described above. Thedistal base 230 acts as a stop surface at the end of the traversal.

FIG. 29 is an illustrative cross-sectional view of a portion of the endeffector 210 showing the first jaw 214 and the drive member 250 duringreturn of the drive member 250 to the start position in accordance withsome embodiments. After all of the staples have been pushed out and thepusher shuttle 244 has reached the distal base 230, the drive screwrotation is reversed so as to move the drive member 250 longitudinallyin a proximal direction back to the start position. During the reversetraversal, the first and second transverse beams 260, 262 cooperate toexert inward force on the second and fourth clamping edges 252-2, 254-2as described above.

FIG. 30 is an illustrative cross-sectional view of a portion of the endeffector 210 showing the first jaw 214 and the drive member 250 in acomplete configuration with the drive member 250 back in the to thestart position in accordance with some embodiments. The drive memberfirst transverse beam 260 is disengaged from both the rotation camsurface 259 and from the first jaw clamping cam surface 252 first jawflat cam surface 252. In accordance with some embodiments, a spring (notshown) can be used to re-open the jaws, causes the first jaw 214 to moveto an open position. The pusher shuttle 244 has been left behind inabutment against the distal base 230.

FIG. 31 is an illustrative drawing showing a lockout mechanism inaccordance with some embodiments. The lockout mechanism comprises alockout spring 297 that flexes in a proximal direction but does not flexin the distal direction The spring 297 is initially biased due tointeraction with the drive member 250 so as to be recessed against alateral side of the second jaw 216 when a reload cartridge 218 isinstalled. During firing of staples, the drive member 250 is driventoward the distal end of the cartridge 218 to discharge the staples.Since the lockout spring 297 is initially recessed against the lateralside of the second jaw 216, it does not block passage of the drivemember 250 during its initial drive toward the distal end of the secondjaw 216. When the drive member 250 member is returned to its initialposition, the spring 297 flexes proximally against the lateral side ofthe second jaw 216, allowing the drive member 216 to pass over it. Oncethe drive member passes over the spring 297, the spring snaps outpreventing the drive member 250 from advancing again toward the distalend of the second jaw 216.

FIGS. 32A-32B are illustrative drawings showing details of the twodegree of freedom wrist 208 of the end effector 210 with the torquetransmitting mechanism 102 in an inline position (FIG. 32A) and in aarticulated position (FIG. 32B) in accordance with some embodiments. Thedrive shaft 104 extends through the center of the driven shaft 106 andengages with the coupling member 108 and the drive shaft plastic bearing128 as described above. First arms 294 depend proximally from oppositesides of the base 212 of the end effector 210. Each arm defines a pairof islets 295. Hypotubes 290 extend longitudinally within the main shaft206 about the drive axis and define hooks 296 at their proximal endsthat engage the islets 295. Second arms 298 extend distally from themain shaft offset ninety degrees form the first arms to define a clevis.The first and second arms 294, 298 enable a pitch and yaw pivot, whichallows the assembly to act as a wrist 208 with two degrees of freedomwhile maintaining the center hollow for the cardan. In operation, andarms 294 enable yaw (up and down movement from the perspective of thedrawing), and arms 298 enable pitch (left to right movement from theperspective of the drawing), Operation of the wrist 292 will beunderstood from U.S. Pat. No. 8,852,174, which is incorporated byreference above.

The foregoing description and drawings of embodiments in accordance withthe present invention are merely illustrative of the principles of theinvention. Therefore, it will be understood that various modificationscan be made to the embodiments by those skilled in the art withoutdeparting from the spirit and scope of the invention, which is definedin the appended claims.

The invention claimed is:
 1. A surgical instrument comprising: a base; afirst jaw having a first jaw axis and that includes a proximal portionpivotally mounted to the base to be pivotable about a pivot axis betweenan open and a closed positions and including a distal portion; a secondjaw having a second jaw axis and including a proximal portion secured tothe base and including a distal portion; a first cam surface secured tothe first jaw that includes a distal cam portion that extends parallelto the first jaw axis and a proximal rotation cam portion that isinclined at an angle relative to the distal cam portion; a second camsurface secured to the second jaw that extends parallel to the secondjaw axis; a drive member including a cross-beam, which is sized toslideably engage the first and second cam surfaces, a first transversebeam portion, and a second transverse beam portion; and a lead screwconfigured to advance the drive member in a distal direction parallel tothe second jaw axis; wherein while the first jaw is in the openposition, the proximal rotation cam portion and the second cam surfaceare disposed to contact the first and second transverse beam portions,respectively, and the proximal rotation cam portion is disposed toimpart a rotational force to the first jaw about the pivot axis as thelead screw advances the drive member in the distal direction; andwherein while the first jaw is in the closed position, the distal camportion and the second cam surface are disposed, to contact the firstand second transverse beam portions, respectively, and to impart a clampforce to the first and second jaws as the lead screw advances the drivemember in the distal direction; a metal drive shaft, including aproximal portion and a distal portion and including a first clevis atthe distal portion of the drive shaft, the first clevis including firstopposed facing arms therein, the drive shaft defining first opposedfacing holes therein, the drive shaft configured to impart a rotationaldrive force; a metal driven shaft, including a proximal portion and adistal portion and including a second clevis at the proximal portion ofthe driven shaft, the second clevis including second opposed facing armsdefining second opposed facing holes therein, the driven shaftconfigured to impart the rotational drive force to the lead screw; auniversal double joint including: a metal sleeve member defining aproximal end opening and a distal end opening; a first metal cross pindefining a first cross pin bore; a second metal cross pin defining asecond cross pin bore; a first rotatable bearing including a firstspherical surface formed of a plastic material, sized to fit within theproximal end opening of the sleeve member for smooth rotation therein,including a first axial engagement structure, and defining a distalopening and a first transverse bore, the first clevis extending withinthe distal opening such that the first opposed facing holes align withthe first transverse bore; the first cross pin extending within thealigned first opposed facing holes and the first transverse bore, suchthat the first cross pin couples the first rotatable plastic bearing torotate in unison with the metal drive shaft; a second rotatable bearinghaving a second spherical surface formed of a plastic material, sized tofit within the distal end opening of the sleeve member for smoothrotation therein, including a second engagement structure, and defininga proximal opening and a second transverse bore, the second clevisextending within the proximal opening such that the second opposedfacing holes align with the second transverse bore; the second cross pinextending within the aligned second opposed facing holes and the secondtransverse bore, such that the second cross pin couples the secondrotatable plastic bearing to rotate in unison with the metal drivenshaft; a first metal coupling pin extending through the first cross pinbore and rotatable within the first cross pin bore, configured to impartthe drive force from the first cross pin mounted in the first clevis tothe sleeve member; and a second metal coupling pin extending through thesecond cross pin bore and rotatable within the second cross pin bore,configured to impart drive force from the sleeve member to the secondcross pin mounted in the second clevis; the first and second axialengagement structures configured to engage each other.
 2. The surgicalinstrument of claim 1, wherein the first jaw is detachably secured tothe base.
 3. The surgical instrument of claim 1, wherein the first jawis integrally secured to the base.
 4. The surgical instrument of claim1, wherein the second jaw is detachably secured to the base.
 5. Thesurgical instrument of claim 1, wherein the second jaw is integrallysecured to the base.
 6. The surgical instrument of claim 1, wherein thedrive member defines a threaded bore therethrough contoured to rotatablyengage the lead screw.
 7. The surgical instrument of claim 1 furtherincluding: a spring disposed to urge the first and second jaws to anopen position before the lead screw advances then drive member thedistal direction.
 8. The surgical instrument of claim 1, wherein thefirst axial engagement structure includes a first spherical gearstructure; and wherein the second axial engagement structure includes asecond spherical gear structure.
 9. The surgical instrument of claim 1,wherein the second jaw includes a staple cartridge.
 10. The surgicalinstrument of claim 1, wherein the first jaw includes an anvil; andwherein the second jaw includes a staple cartridge.
 11. The surgicalsystem of claim 10, wherein the staple cartridge includes a knife edge.12. The surgical instrument of claim 1, the first axial engagementstructure including first gear teeth; and the second axial engagementstructure including second gear teeth.
 13. The surgical instrument ofclaim 1, the first axial engagement structure including first gearteeth; and the second axial engagement structure including second gearteeth; the first gear teeth and the second gear teeth are sphericallyoriented to eliminate rotational speed differences between the driveshaft and the driven shaft.
 14. The surgical instrument of claim 1, thefirst rotatable bearing is formed of injection molded plastic material;and the second rotatable bearing is formed of injection molded plasticmaterial.
 15. The surgical instrument of claim 1, the first rotatablebearing defining a slot sized to permit passage of the first couplingpin during rotation of the first cross pin within the first clevis; andthe second rotatable bearing defining a slot sized to permit passage ofthe second coupling pin during rotation of the second cross pin withinthe second clevis.
 16. The surgical instrument of claim 1, wherein thefirst cross pin is rotatable relative to the first opposed facing holesand is rotatable relative to the first transverse bore; and wherein thesecond cross pin is rotatable relative to the second opposed facingholes and is rotatable relative to the second transverse bore.